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Biomedical subjects

K C Conlon

Publications and source records attributed to K C Conlon.

At least 55 records · Page 3Linked to original sources
PubMed1996

Phase I study of subcutaneously administered interleukin-2 in combination with interferon alfa-2a in patients with advanced cancer.

PURPOSE: Although high-dose interleukin-2 (IL-2) can produce durable remissions in a subset of responding patients with renal cell carcinoma (RCC), this occurs in the setting of significant toxicity. The purpose of this study is to define the maximum-tolerated dosage (MTD) of IL-2 and interferon alfa-2a (IFN alpha-2a) that can be administered chronically on an outpatient basis. PATIENTS AND METHODS: Fifty-three patients with advanced cancer of variable histology with good prognostic features were treated in six cohorts. Patients in cohorts one through five received IL-2 (1.5 or 3.0 x 10(6) million units (mU)/m2) Monday through Friday and IFN alpha-2a (1.5 or 3 x 10(6) mU/m2) daily for a 4-week cycle. In cohort six, IFN alpha-2a was given three times a week. Immunologic monitoring, including serum levels of soluble IL-2 receptor (sIL-2R) and neopterin, flow cytometry, and natural killer cell (NK) activity, were measured. Patients were evaluated for toxicity, response, and survival. RESULTS: Almost all patients developed grade I/II toxicities commonly associated with cytokine therapy. Symptoms were most severe with the first treatment of each week. Dose-limiting toxicities included grade III fatigue, hypotension, and creatinine elevations. The MTD was 1.5 mU/m2 daily x 5 given subcutaneously repeated weekly for IL-2 and 1.5 mU/m2 daily subcutaneously (dose level 3) for IFN. Six of 25 assessable patients with RCC (24%) achieved a partial response (PR), including four of eight patients who were previously untreated. There were no objective responses in patients with other tumors, including 12 melanoma patients. CONCLUSION: IL-2 and IFN alpha-2a can be given with tolerable toxicities on an outpatient basis and shows significant activity in patients with metastatic RCC.

Adult↗
PubMed1996

Laparoscopy and laparoscopic ultrasound in the staging of gastric cancer.

As patients with gastric cancer are offered choices between surgical resection, investigational neoadjuvant chemotherapy, palliative chemotherapy, or symptomatic relief alone, the need for accurate preoperative staging becomes apparent. Laparoscopy has been suggested as an accurate staging modality in a variety of upper gastrointestinal malignancies. It allows for assessment of the stage of the primary tumor, identification of hepatic or regional nodal metastases, and the detection of small volume peritoneal disease unappreciated by other noninvasive staging modalities such as computerized tomography, magnetic resonance imaging or endoscopic ultrasound. This article reviews the current literature concerning laparoscopy and laparoscopic ultrasonography (LUS) in the staging of gastric cancer. The Memorial Hospital experience with 92 patients is described. In this group, metastatic disease unappreciated by conventional staging modalities was found in 31 cases. The preliminary experience with LUS suggests that its addition to standard laparoscopy increases the sensitivity and specificity of M1 screening as well as introducing T and N staging capabilities.

Gastroscopy↗
PubMed1995

Laparoscopic resection of a giant omental cyst.

Omental and mesenteric cysts are uncommon, requiring surgical intervention when symptomatic. A report of a giant primary omental cyst successfully treated utilizing minimal-access surgical techniques is presented. The laparoscopic approach allowed complete, intact excision of the cyst, while decreasing operative morbidity and hospital stay.

Adult↗
PubMed1995

Primary gastrointestinal sarcomas: analysis of prognostic variables.

BACKGROUND: Primary gastrointestinal sarcomas are uncommon, and the clinicopathological determinants of survival remain unclear. In order to correlate clinical presentation, pathological assessment, and treatment with outcome, we have analyzed our institution's recent experience with these tumors. METHODS: Records of adult patients admitted to our institution between July 1982 and December 1991 were reviewed. RESULTS: During this period, 38 adult patients (> 16 years of age) were admitted to our institution with a primary gastrointestinal sarcoma. They accounted for 2% of all adult sarcoma admissions during that period. The study population was composed of 26 men and 12 women. Ages ranged from 29 to 82 years (mean 59). Disease was localized to the primary site in 30 patients (81%). The stomach was the most frequent site of disease (20 cases). The small bowel was affected in nine cases (five duodenum, four jejunum) and the large bowel in nine cases (two colon, seven rectum). Ninety-two percent of patients were symptomatic at presentation. A complete resection was performed in 27 cases, incomplete resection in seven cases, and biopsy only in the remaining three patients. Nine patients received doxorubicin-based chemotherapy. Leiomyosarcoma (n = 35) was the predominant histological diagnosis. Twenty-six tumors were classified as high grade (68%) and 12 as low grade (32%). Overall actuarial 5-year survival was 28% (median follow-up 26 months). Weight loss (p = 0.02) and pain at presentation (p = 0.05) were adverse prognostic factors. Histological grade (p = 0.0002), completeness/extent of surgical resection (p = 0.005), or small bowel primary site were significant determinants of overall survival. The resection of contiguous organs did not affect survival if the primary tumor was completely excised (p = 0.422). Age, race, sex, presentation (prior surgery), tumor size, or adjuvant therapy were not significant prognostic factors. Recurrence was noted in 44% after complete resection, and mean time to recurrence was 9 months (median 7, range < 1-37). Hepatic metastases (42%) and local recurrence (42%) were the predominant sites of initial failure. For patients with a complete resection, grade was the major prognostic determinant (5-year survival: high grade/complete resection 18% vs. low grade/complete resection 72%, p = 0.002). CONCLUSION: The prognosis of gastrointestinal sarcomas is poor. Complete surgical excision is the optimal therapy. However, our results suggest that surgery alone is inadequate for high-grade tumors. We believe that these patients should be considered candidates for investigational adjuvant therapies.

Adolescent↗
PubMed1994

Primary squamous cell carcinoma within a solitary nonparasitic hepatic cyst.

A case report is presented of a patient who developed primary squamous cell carcinoma in a solitary nonparasitic hepatic cyst. The clinical presentation, operative management, and pathological findings are discussed. This case is unusual as the histology demonstrates transition from columnar cell architecture through squamous cell metaplasia and carcinoma in situ to invasive carcinoma.

Carcinoma, Squamous Cell↗
PubMed1994

The effect of prolonged hyperglycemia on metabolic alterations in the subtotally pancreatectomized rat.

A delayed onset of diabetes is characteristic of subtotally pancreatectomized patients in whom persistent hyperglycemia per se is documented to lead to the development of insulin resistance. This study was conducted to elucidate the metabolic alterations seen during transition of the acute to chronic phase after subtotal pancreatectomy (SP). Eight male Sprague-Dawley rats were studied 2 weeks after surgery in the acute phase, and the other eight at 4 weeks in the chronic phase. Phosphoenolpyruvate carboxykinase (PEPck) for gluconeogenesis and the malic enzyme for de novo fatty acid synthesis in the liver showed a reciprocal change, the former activity being increased, while the latter was suppressed. Both alterations were more pronounced in the chronic phase. In the acute phase, lipoprotein lipase (LPL) for triglyceride clearance decreased in the adipose tissue, while that in the cardiac and skeletal muscle became significantly elevated. The latter elevations were decreased in the chronic phase. Sustained hyperglycemia in the SP rats not only increased the changes in PEPck and malic enzyme activities but reversed the tissue-specific muscle LPL elevations. These changes might help to explain the wasting condition seen in surgically induced diabetic patients.

Adipose Tissue↗
PubMed1994

Comparison of transcutaneous oximetry and laser Doppler flowmetry as noninvasive predictors of wound healing after excision of extremity soft-tissue sarcomas.

BACKGROUND: We wished to determine whether transcutaneous oximetry or laser Doppler flowmetry (LDF) could identify patients at risk for wound failure after conservative, limb-sparing surgery for extremity sarcomas. METHODS: Studies were performed on postoperative days (PODs) 1, 4/5, 7, and 9. Measurements of transcutaneous oxygen pressure (tcPO2) were taken at breathing room air (BL) and 100% oxygen (rate tcPO2). LDF measurements were taken at multiple sites along the wound, and a perfusion index was calculated. RESULTS: Twenty-four patients were studied. Four (17%) had nonhealing wounds. There was no difference in tcPO2 (BL) values between healed and nonhealing wounds. Measurement of rate tcPO2 on POD 1 was significantly lower in the nonhealing wounds than in those with normal healing (28.5 +/- 12.1 mm Hg vs 14.3 +/- 16.2 mm Hg, mean +/- SD, p = 0.03). Rate tcPO2 values increased significantly in healing wounds from POD 1 to PODs 7 and 9 (p = 0.006, p = 0.009). This increase was absent in nonhealing wounds. A clear separation was noted in rate tcPO2 values between groups, with a minimum rate tcPO2 value recorded in a healed wound of 9 mm Hg/min, compared with the maximum value in a nonhealing wound of 7 mm Hg/min. The LDF perfusion index failed to predict wound healing at any of the measured time points. CONCLUSIONS: This study showed that measurement of tcPO2 during oxygen inhalation can accurately predict wound healing in patients after excision of an extremity sarcoma.

Adult↗
PubMed1993

Engraftment and activity of anti-CD3-activated human peripheral blood lymphocytes transferred into mice with severe combined immune deficiency.

Human PBL (huPBL) were activated with anti-CD3 mAb in vitro and then were transferred into mice with severe combined immune deficiency (SCID) to determine the effect of activation on engraftment and to determine if the engrafted human cells could provide antitumor effects in mice. Some mice were also treated with human rIL-2 after huPBL transfer. Mice were analyzed 6 to 8 wk after cell transfer and the number of human cells in the peripheral lymphoid organs was determined. Mice receiving anti-CD3-activated huPBL demonstrated a significant increase in the incidence of human T cell engraftment in the periphery as assessed by flow cytometry. Human cells were also detected in the murine thymus after anti-CD3 stimulation indicating that human T cells can migrate to the murine thymus provided that they are activated before the transfer. The transfer of anti-CD3-activated huPBL also resulted in an xenogeneic graft-vs-host reaction manifested primarily by proliferation of murine splenic hemopoietic cells. When SCID mice received the human colon carcinoma HT29, the concurrent transfer of anti-CD3-activated human cells resulted in a significant increase in survival. However, the human cells displayed low cytolytic activity toward human tumor targets when they were recovered from the lymphoid organs of the SCID recipients. Supernatants from the anti-CD3-activated cells were able to inhibit the growth of HT29 in vitro, partly because of the presence of IFN-gamma, suggesting that the human T cells are producing cytokines in vivo that have antitumor effects. Thus, the use of anti-CD3-activated huPBL in SCID mice may be of value for optimizing human cell engraftment in the human/mouse lymphoid chimeras and may be used to evaluate potential anti-neoplastic therapies that employ human effector cells.

Animals↗
PubMed1993

Extremity metabolism in the cachectic, VX-2 carcinoma-bearing rabbit.

The pathophysiology of skeletal muscle loss in cancer cachexia is poorly understood. Immature, male, New Zealand White rabbits (TBs; n = 11) were implanted with VX-2 carcinoma and various indices of systemic and limb metabolism were examined in comparison with pair-fed controls (PFCs; n = 9) and normal controls (NCs; n = 22) fed ad lib. The TBs became hypophagic and experienced reduced growth relative to both control groups (P << 0.001). At 7 weeks (tumor burden 3-6% of body weight; no metastasis) the TBs had the following statistically significant differences from NCs: anemia, neutrophilic granulocytosis and thrombocytosis, hypercalcemia, hypoinsulinemia, elevated plasma triglycerides and altered plasma amino acids, increased hind limb effluxes of lactate and most amino acids. These alterations were not caused by hypophagia, since the PFCs were normal at 7 weeks with regard to all measured parameters except body weight and limb flow, both of which were reduced. The decrease in flow (P < 0.05) apparently contributed to conservation of skeletal muscle amino acids in the PFCs. Young New Zealand White rabbits implanted with VX-2 carcinoma manifest tumor burden, wasting, and metabolic alterations qualitatively similar to those seen with many human cancers.

Amino Acids↗
PubMed1993

Antitumor effects of interleukin-7 and adoptive immunotherapy on human colon carcinoma xenografts.

The antitumor properties of recombinant human IL-7 (rhIL-7) on a human tumor was evaluated by engrafting a human colon carcinoma into immunodeficient mice and then treating the mice with rhIL-7 and adoptively transferred human peripheral blood T cells. It was found that rhIL-7 alone had no effect on the survival of the tumor-bearing recipients. However, the combination of rhIL-7 and human T cells significantly promoted the survival of the recipients compared with mice receiving either treatment by itself. When the surviving mice were analyzed 6 mo later for the degree of human cell engraftment, the recipients receiving both rhIL-7 and human T cells had greater numbers of human CD8+ T cells in the spleens. However, the human T cells recovered from the surviving mice showed low lytic activity against the tumor in vitro. Supernatants from human T cells cultured with the tumor and rhIL-7 in vitro were found to inhibit tumor growth and were demonstrated to contain high levels of IFN-gamma. Antibodies to IFN-gamma neutralized the growth inhibition of the tumor both in vitro and in vivo demonstrating that the in vivo mechanism underlying the antitumor effects of this regimen was partly dependent on the production of IFN-gamma by the T cells and not their cytolytic capability. Interestingly, systemic administration of rhIFN-gamma to tumor-bearing mice yielded little antitumor effect suggesting that adoptive immunotherapy with rhIL-7 was superior possibly because of the continuous local release of the cytokines. Therefore, rhIL-7 may be of clinical use as an antineoplastic agent and the human/mouse model is a potentially important preclinical model for in vivo evaluation of the efficacy of this and other immunotherapies.

Animals↗
PubMed1993

Treatment of cancer patients with ex vivo anti-CD3-activated killer cells and interleukin-2.

PURPOSE: This study describes the physiologic and biologic effects resulting from the adoptive transfer of ex vivo anti-CD3-stimulated T-killer cells (T-AK) to patients with advanced cancer in combination with interleukin-2 (IL-2). METHODS: Autologous peripheral-blood mononuclear cells were obtained by leukapheresis and stimulated ex vivo with anti-CD3. The stimulated cells were reinfused at one of three dose levels on the next day (5 x 10(9), 7.5 x 10(9), and 1 x 10(10)). Cell administration was followed by IL-2 given by bolus and continuous infusion (1.5 x 10(6) U/m2 and 3.0 x 10(6) U/m2, respectively) for 7 days, or continuous infusion alone (3.0 x 10(6) U/m2) for 14 days. RESULTS: Pronounced leukocytosis and atypical lymphocytosis were observed with individual values as high as 80,000 and 50,000 cells/microL, respectively. The other major clinical sequelae included a marked lactic acidosis with bicarbonate levels as low as 4.0 mmol/L in some patients, and prolongation of the prothrombin time (PT) and partial thromboplastin time (PTT) due to decreases in clotting factors VII, IX, and X. Antithrombin III levels were also reduced. Hypotension associated with increased serum nitrate and neopterin levels was observed. These toxicities were accompanied by increases in hepatocellular enzymes and creatinine previously described with IL-2. These events occurred at a time when the number of circulating T-AK cells reached their peak. The amount of bolus IL-2 correlated with increases in WBC count (P = .0311), atypical lymphocytes (P = .0241), PT (P = .0006), and PTT (P = .0122). CONCLUSION: Substantial in vivo expansion of activated T lymphocytes was induced by a protocol combining ex vivo activation of peripheral-blood cells with anti-CD3 antibody followed by adoptive transfer and IL-2 administration. The synchronous expansion of these T cells superimposed on diminished liver and kidney function from IL-2 can cause profound but reversible metabolic changes.

Acidosis↗
PubMed1992

Enhanced lymphokine production and lymphokine receptor expression in multiple antibody-stimulated human CD4+ peripheral blood lymphocytes.

Treatment of T lymphocytes with antibodies directed against the T cell receptor CD3 complex results in cellular activation that can be augmented by costimulation through other cell surface receptors. The activities of anti-CD3-stimulated human CD4+ PBL were compared to anti-CD3 plus anti-CD2-, anti-CD4-, or anti-CD11a (LFA-1)-stimulated cells. [3H]thymidine incorporation, lymphokine receptor expression, expansion of cell numbers, and lymphokine mRNA and protein were measured. Forty-eight hours after activation, costimulated CD4+ cells demonstrated increased numbers of cells positive for surface IL-2R alpha-chain, IL-2R beta-chain, IFN-gamma receptors, and TNF-alpha receptors. By day 6, costimulated cells exhibited a sevenfold greater expansion in cell numbers compared to cells stimulated with anti-CD3 alone. Anti-CD3 plus anti-CD11a stimulation consistently induced the highest secretion of IL-2 and IFN-gamma, whereas variation in secretion of TNF-alpha and IL-4 between different donors was noted. Analysis of lymphokine receptor mRNA demonstrated increased levels of mRNA for IL-2R alpha-chain and IFN-gamma receptor that preceded the phenotypic changes on the cell surface. In contrast, levels of IL-2R beta-chain and the TNF-alpha receptor mRNA decreased after stimulation. Amounts of IL-2, IL-4, and TNF-alpha, but not IFN-gamma, secreted also correlated with the levels of mRNA measured in the cells. Although costimulation through CD2, CD4, or LFA-1 appeared equally effective for the induction of the lymphokine receptors, these additional stimuli had a different impact on lymphokine secretion. These results indicate that specific control of lymphokine secretion and receptor induction can be another function of the CD2, CD4, and CD11a cell surface receptors. This control is evident at both transcriptional and post-transcriptional levels.

Antibodies↗
PubMed1992

The toxic and hematologic effects of interleukin-1 alpha administered in a phase I trial to patients with advanced malignancies.

PURPOSE: A phase I trial was undertaken because interleukin-1 alpha (IL-1 alpha) possesses antiproliferative, immunostimulatory, antiinfection, myeloprotective, and myelorestorative properties that could be beneficial in cancer treatment. PATIENTS AND METHODS: In this phase I trial, IL-1 alpha was administered intravenously (IV) during a 15-minute period daily for 7 days to patients with advanced solid malignancies. RESULTS: The maximum-tolerated dose (MTD) of IL-1 alpha alone was 0.3 microgram/kg. A second group of patients received indomethacin plus IL-1 alpha based on preclinical studies, which indicated that indomethacin could abrogate IL-1 alpha-induced hypotension; however, the MTD of IL-1 alpha plus indomethacin was 0.1 microgram/kg lower than IL-1 alpha alone. Fever, chills, headache, nausea, vomiting, and myalgia were common but were not dose-limiting. Hypotension resulted from a marked decrease in systemic vascular resistance and required pressors at 0.3 and 1.0 micrograms/kg IL-1 alpha. Dose-limiting toxicities included hypotension, myocardial infarction, confusion, severe abdominal pain, and renal insufficiency. IL-1 alpha treatment caused a significant, dose-related increase in the total WBC count (mainly segmented neutrophils and neutrophilic bands). Bone marrow cellularity increased because of enhanced numbers of relatively mature myeloid cells and megakaryocytes. Platelet counts decreased during therapy but were significantly elevated above baseline values 1 to 2 weeks posttreatment; this may have been an effect of IL-6 that was shown to be induced by IL-1 alpha treatment. Significant increases in triglycerides, cortisol, C-reactive protein, thyroid-stimulating hormone and decreases in cholesterol, testosterone, and protein-C were observed with treatment. CONCLUSION: We conclude that at doses of IL-1 alpha that can be given safely to cancer patients, significant, potentially beneficial hematopoietic effects occur.

Adult↗
PubMed1991

Prolonged, continuous treatment of hairy cell leukemia patients with recombinant interferon-alpha 2a.

Interferons are not curative in hairy cell leukemia (HCL), and retreatment is necessary in most patients whose therapy is stopped. In an attempt to maintain or improve responses, we administered recombinant interferon-alpha 2a (rIFN-alpha 2a) continuously to patients with HCL who initially responded to this therapy. Of 53 evaluable patients enrolled in this study, 32 have received rIFN-alpha 2a continuously for a median of 5 years. Patients received 3 million units of rIFN-alpha 2a subcutaneously (SC) daily for 6 months, followed, in responding patients, by the same dose three times weekly. Twenty-one patients (40%) discontinued IFN after a median of 29 months, seven of whom developed resistant disease in association with anti-IFN antibodies. Treatment produced high response rates: complete response plus partial response (CR + PR) = 40 of 53 (76%), CR + PR + minor response (MR) = 43 of 53 (82%), with no differences in response rates between patients with and without splenectomy. Sixteen patients who had MR at 18 months had PR with prolonged treatment, nine of whom had a significant further reduction in the hairy cell infiltrate in the bone marrow (BM). The median granulocyte and platelet counts have continued to increase and the median serum soluble interleukin-2 receptor (sIL-2R) level has continued to decrease with prolonged treatment. Two patients developed erythrocytosis that may be treatment related, but no other new toxicities were noted with prolonged treatment. We conclude that prolonged, continuous rIFN-alpha 2a treatment has acceptable toxicity, is not associated with late development of IFN resistance, and results in continued hematologic improvement with time on treatment.

Adult↗
PubMed1991

Phase I evaluation of recombinant tumor necrosis factor given in combination with recombinant interferon-gamma.

In light of in vitro and preclinical animal model data suggesting potential additive or synergistic antitumor effects from the combined use of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), we conducted a phase I study employing escalating doses of each agent in 36 patients with solid tumors to determine the maximum tolerated dose (MTD). Patients were given an intramuscular (i.m.) injection of IFN-gamma, followed 5 min later by an i.m. injection of TNF-alpha, each agent in different sites, every other day for ten doses over 20 days. Patients received 10, 50, or 100 micrograms/m2 of each agent throughout the treatment course. No dose modifications were made. Patients suffering serious toxicity had therapy stopped and were considered to be off-study. All patients experienced fatigue, and 36% spent over half their time in bed on treatment days. Fever and chills were nearly universal. Mild to moderate elevations in serum transaminase levels were noted in 44% of patients, and 44% developed transient microscopic hematuria. Although 81% of patients had anorexia, only 17% of patients lost more than 3 kg of body wt during the 3 weeks of therapy. Because two of three patients receiving 100 micrograms/m2 of both agents developed serious toxicity (one fever greater than 105 degrees F, one thrombocytopenia 43,000/mm3), the MTD was established to be 100 micrograms/m2 of IFN-gamma plus 50 micrograms/m2 of TNF-alpha. The use of aspirin did not significantly alter the toxic effects of the agents. One patient with melanoma had a mixed response and one patient with mesothelioma transiently cleared his ascites of malignant cells.

Adult↗